Process of extracting tanning substances.



No. 794,847. PATENTED JULY 18, 1905. G. F. BUGEL.

PROCESS OF EXTRAOTING TANNING SUBSTANCES.

APPLIOATION FILED PEB.19,1902.

Aurmiw a. unmm 0a., umocmwzas, WASHINGTON, n c

NITED STATES Patented July 18, 1905.

PATENT OFFICE.

PROCESS OF EXTRACTING TANNING SUBSTANCES.

SPECIFICATION forming part of Letters Patent No. 794,847, dated July 18,1905.

Application filed February 19, 1902. erial No. 94,732.

To all whom it may concern.-

Be it known that I, Gnone FERDINAND Bo- GEL, a subject of the King ofPrussia, German Emperor, residing at Altona, Germany, have invented newand useful Improvements in Processes of Extracting Tanning Substances,of which the following is a specification.

This invention relates to a process for the continuous extraction oftanning materials within a battery 'of centrifugals. To obtain athorough extraction, even with short batteries, only a part of thesubstances thrown off from one centrifugal is conveyed to the succeedingcentrifugal, while the remainder is returned to the firstcentrifugal.Thecomminuted tanning material is introduced into a number ofcentrifugals placed side by side. Fresh water is supplied to one of thecentrifugals, which by the rotation of the latter is driven through thelayer of tanning material that accumulates upon its wall, so that thewater becomes enriched by the tannin. The thrown-ofi and accumulated lyeis then pumped partly into the next centrifugal and partly back into thefirst centrifugal, where it is again driven through the layer of tanningmaterial, and so on through the entire series. From the last centrifugalhalf of the lye passes into the discharge-pipe, while the other halfpasses back into'the last centrifugal. In this way a complete extractionof the tanning material may be obtained without injuriously afiectingthe same.

In the accompanying drawings, Figure 1 is a plan of an apparatus forcarrying my invention into effect; Fig. 2, a section on line G H, Fig.1; and Fig. 3 an elevation at right angles to Fig. 2.

The letter 0 represents the first of a series of centrifugals, which issupposed to be disconnected from the other centrifugals of the battery,so that it may be filled with fresh tanning material. The valve (Z isopened, and fresh water flows to the centrifugal a The rotation of thecentrifugal (6 drives this water through the tanning material thrownagainst the wall of the centrifugal, so as to become saturatedtherewith. The tossed liquid then accumulates upon the bottom of thefixed vessel which surrounds the centrifugal and passes through the ductg to the pump f. The pump conveys the liquid through pipe 72 to union 2'from which one half of the liquid is carried by pipe 6 to centrifugal awhile the other half is carried by pipe I? to centrifugal (0 The liquidreturned to the centrifugal a is mixed with the fresh water admitted tothe same and is driven through the layer of tanning material in themanner above described, to be again conveyed in equal parts to thecentrifugal a and centrifugal (6 The somewhat enriched lye carried tocentrifugal a is here again driven through the layer of tanning materialthrown against the wall of the centrifugal to become further enriched.The lye then accumulates on the bottom of the fixed vessel whichsurrounds the centrifugal and passes through the duct 9 to pump f whichconveys it through pipe a to union From this union one half of theliquid is returned by pipe Z to centrifugal a and the other half isconveyed by pipe k to centrifugal a. Within the centrifugal a theoperation is repeated, and the agitated and now finished lye is pumpedthrough pipe l, partly back to centrifugal a and partly through pipe todischarge-pipe n. The extracting operation is repeated in the abovemanner until the contents of centrifugal a are completely leached, whenthe valve (Z is closed and the pipe 7:? is placed over the inlet-funnelof pipe 0, while the pipe It" is placed over the inletfunnel 922/ of thedischarge-pipe n and the valve (Z is opened. The fresh water will nowflow to the centrifugal a", is here thrown through the layer of tanningmaterial and collected at the bottom of the centrifugal, to be carriedby pump f and pipe k to union 2 From this union one half of the liquidpasses by pipe Z back to centrifugal (3, while the other half passes bypipe 76 to centrifugal a. In centrifugal a the process is repeated andthe agitated lye is carried by pump f and pipe h to union 71*. From thisunion one half of the liquid is conveyed by pipe 7t" back to centrifugala, while the other half is conveyed by pipe 0 to centrifugal a. Afterthe lye has then been thrown through the layer of tanning material incentrifugal a the now finished lye is conveyed through pump f andconduits h i Z, one half back to centrifugal a and the other halfthrough conduits h 1," l0 to funnel m of the discharge-pipe. Theextraction thus takes place in the centrifugals a a, and a, While thecentrifugal a is ready to be filled with fresh tanning material for aperiod sufiicient to permit the complete extraction of the tanningmaterial in the centrifugal a If this extraction has taken place, thevalve d is closed and the pipe is is placed over the centrifugal (0While the pipe 70 is placed over the inlet-funnel m of thedischarge-pipe n. The Valve d is also opened,

so that the extracting process will be carried "on in the centrifugalsa, a, and (6 While the centrifugal a may be filled With fresh tanningmaterial. In this Way the separate centrifugals may be successivelyfilled Without Signed at Hamburg, Germany, this 5th day 3 of February A.D. 1902.

' GEORG FERDINAND BOGEL.

Witnesses:

MAX FOUGUCT, E. H. L. MUMMENHOFF.

